We study iteration and recursion operators in the denotational semantics of typed λ-calculi derived from the multiset relational model of linear logic. Although these operators are defined as fixpoints of typed functionals, we prove them finitary in the sense of Ehrhard’s finiteness spaces.

Proof systems with sequents of the form
U ⊢ Φ for
proving validity of a propositional
modal μ-calculus formula Φ over a set U of
states in a given model usually handle
fixed-point formulae through unfolding, thus allowing such formulae
to reappear in a proof. Tagging is a technique originated by Winskel
for annotating fixed-point formulae with information
about the proof states at which these are unfolded. This information
is used later in the proof to avoid unnecessary unfolding, without...

The work concerns formal verification of workflow-oriented software models using the deductive approach. The formal correctness of a model's behaviour is considered. Manually building logical specifications, which are regarded as a set of temporal logic formulas, seems to be a significant obstacle for an inexperienced user when applying the deductive approach. A system, along with its architecture, for deduction-based verification of workflow-oriented models is proposed. The process inference is...

We introduce algorithmic logic - an algebraic approach according to [25]. It is done in three stages: propositional calculus, quantifier calculus with equality, and finally proper algorithmic logic. For each stage appropriate signature and theory are defined. Propositional calculus and quantifier calculus with equality are explored according to [24]. A language is introduced with language signature including free variables, substitution, and equality. Algorithmic logic requires a bialgebra structure...

Motivation for this paper are classification problems in which data can not be clearly divided into positive and negative examples, especially data in which there is a monotone hierarchy (degree, preference) of more or less positive (negative) examples. We present a new formulation of a fuzzy inductive logic programming task in the framework of fuzzy logic in narrow sense. Our construction is based on a syntactical equivalence of fuzzy logic programs FLP and a restricted class of generalised annotated...

We give a new proof showing that it is not possible to define in monadic second-order logic (MSO) a choice function on the infinite binary tree. This result was first obtained by Gurevich and Shelah using set theoretical arguments. Our proof is much simpler and only uses basic tools from automata theory. We show how the result can be used to prove the inherent ambiguity of languages of infinite trees. In a second part we strengthen the result of the non-existence of an MSO-definable well-founded...

We study the succinctness of monadic second-order logic and a variety of monadic fixed point logics on trees. All these languages are known to have the same expressive power on trees, but some can express the same queries much more succinctly than others. For example, we show that, under some complexity theoretic assumption, monadic second-order logic is non-elementarily more succinct than monadic least fixed point logic, which in turn is non-elementarily more succinct than monadic datalog.
Succinctness...

We study the succinctness of monadic second-order logic and a variety
of monadic fixed point logics on trees. All these languages are known to have
the same expressive power on trees, but some can express the same
queries much more succinctly than others. For example, we show that, under
some complexity theoretic assumption, monadic second-order logic is
non-elementarily more succinct than monadic least fixed point logic,
which in turn is non-elementarily more succinct than monadic datalog. Succinctness...

Since recognizable tree languages are closed under the rational operations, every regular tree expression denotes a recognizable tree language. We provide an alternative proof to this fact that results in smaller tree automata. To this aim, we transfer Antimirov's partial derivatives from regular word expressions to regular tree expressions. For an analysis of the size of the resulting automaton as well as for algorithmic improvements, we also transfer the methods of Champarnaud and Ziadi from words...

Since recognizable tree languages are closed under the rational
operations, every regular tree expression denotes a recognizable
tree language. We provide an alternative proof to this fact that
results in smaller tree automata. To this aim, we transfer
Antimirov's partial derivatives from regular word expressions to
regular tree expressions. For an analysis of the size of the
resulting automaton as well as for algorithmic improvements, we also
transfer the methods of Champarnaud and Ziadi...